from sympy.abc import n
import sympy
from  sympy import init_printing,init_session,pprint
# init_session(quiet=True)
# init_printing()
# 求E的泰勒展开
# 测试求和
f=1/sympy.factorial(n)
pprint(f)
e=sympy.summation(f,(n,0,sympy.oo))

pprint(e)